Sunday, September 14, 2008

The Ascention of JavaScript

I added a couple of new things to my little JavaScript library (q12). It turns out there was a flaw in the library when making HTTP requests which included custom HTTP headers in Firefox3 (and maybe others). If you ever run into (NS_ERROR_FAILURE) [nsIXMLHttpRequest.setRequestHeader], try opening the HTTP request first (as I recently learned). I've always said that writing this library was for education more than any anticipated serious use.

I also added a function for ARC4 encryption, which doesn't provide strong security, but it is still used in some places.

This has been quite a big month for JavaScript. In just a couple of weeks V8, Tracemonkey, and SquirrelFish Extreme have leapforgged one another and improved the state of JavaScript execution speed. It's gotten me thinking.

The more I use JavaScript, the more I like it. The language itself is extremely simple, I would argue even simpler than C - it's the APIs in browsers which are sometimes complex and inconsistent ;-) With all of these optimizations, JavaScript is looking better and better as a language in which to implement a new dynamic language.

Between the Just In Time compiler (JIT) and the polymorphic inline cache, some state of the art tools are coming to bear on one of the most widely available programming languages today. JavaScript is making strides to overcome a very difficult problem: maintaining complete runtime flexibility while providing speedy execution. There are significant investments being made in JavaScript as a language, and it seems that some of these open source components should be reusable. I'm not sure how much of these libraries would stand alone, but it would be a very interesting experiment to see if a new language could be implemented in JavaScript.